There is an image forming apparatus in which an exposure unit configured to expose a photoconductive drum to light is located below the photoconductive drum. A shutter unit is arranged between the exposure unit and the photoconductive drum in order to prevent a toner from falling and adhering to a light emission surface (e.g., an emission glass) of the exposure unit. When the shutter unit covers the light emission surface of the exposure unit, the adhesion of the toner to the light emission surface can be prevented. When the shutter unit retracts from the light emission surface, a laser beam of the exposure unit is transmitted through the light emission surface and reaches the photoconductive drum.